CRC · California Residential Code

What limits exist for hearth extensions, gasketed doors and decorative shrouds on factory-built systems?

For factory-built fireplaces in California you must follow the appliance’s listing: hearth extensions must be installed per the listing (UL 1618), gasketed doors are forbidden unless the system is specifically listed for them (UL 127), and decorative chimney shrouds are allowed only when listed for that exact system and installed per the manufacturer. **§ R1004.2**, **§ R1004.5**, **§ R1004.3**.

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Last reviewed: July 6, 2026

What the code requires — 2-4 sentences

  • The California Residential Code requires that hearth extensions for factory-built fireplaces be installed exactly as shown in the fireplace’s listing and that listed hearth extensions comply with UL 1618 — the code does not supply alternate dimensions for factory-built units; follow the listing. § R1004.2 .
  • Gasketed fireplace doors may not be added to a factory-built fireplace unless the entire fireplace system has been specifically tested, listed and labeled for that door configuration in accordance with UL 127. § R1004.5 .
  • Decorative shrouds at the chimney termination are prohibited unless the shroud is listed and labeled for that specific factory-built fireplace system and installed per the manufacturer’s instructions. § R1004.3 .

The single most important rule: If the factory-built fireplace or chimney component is not listed and labeled for the accessory or modification (hearth extension design, gasketed door, shroud), the accessory or modification is not permitted. § R1004.2, § R1004.5, § R1004.3

Requirements in detail

Hearth extensions (factory-built fireplaces)

  • Rule: The hearth extension for a listed factory-built fireplace must be installed in accordance with the fireplace listing; a listed hearth extension must comply with UL 1618. § R1004.2 .
  • Practical effect: The installer must use the dimensions, materials and installation details the manufacturer/listing requires. The CRC does not substitute masonry hearth dimensions for factory-built listings.

Decision-relevant values/points:

Decision item What to check / value Code reference
Who sets the extension dimensions Fireplace listing / manufacturer instructions (not generic CRC dimensions for masonry) § R1004.2
Listed hearth standard UL 1618 § R1004.2
Visual distinction requirement Hearth extension must be “readily distinguishable” from surrounding floor § R1004.2

Note: The CRC contains separate hearth-dimension rules for masonry fireplaces (for example, § R1001.10) that specify 16 in. front / 8 in. sides (or 20 in. front / 12 in. sides for large openings) — those masonry dimensions do not override a factory-built fireplace’s listing; confirm which section applies to your unit. § R1001.10

Gasketed doors

  • Rule: A gasketed fireplace door is not permitted on a factory-built fireplace unless the fireplace system has been specifically tested, listed and labeled for that door arrangement in accordance with UL 127. § R1004.5 .
  • Practical effect: You cannot retrofit a gasketed/airtight door onto a factory-built unit unless the manufacturer/listing explicitly allows that door and the listing shows compliance with UL 127.

Decision table:

Decision item What to check / value Code reference
Allowed retrofit of gasketed door? Only if fireplace system is specifically tested/listed for that door § R1004.5
Test standard required UL 127 (factory-built fireplaces) § R1004.5

Decorative shrouds (chimney terminations)

  • Rule: Decorative shrouds shall not be installed at the termination of chimneys for factory-built fireplaces except when the shroud is listed and labeled for use with that specific factory-built fireplace system and is installed per the manufacturer’s instructions. § R1004.3 .
  • Practical effect: Aftermarket or generic shrouds that are not listed for the specific model are not code-compliant; the same limitation is reiterated for factory-built chimneys in Section R1005.2. § R1005.2

Decision table:

Decision item What to check / value Code reference
Can you add a decorative shroud? Only if shroud is listed/labeled for that specific system § R1004.3
Install instructions Must follow manufacturer’s installation instructions § R1004.3
Chimney-level repeat R1005.2 repeats same limitation for factory-built chimneys § R1005.2

Exceptions & special cases

  • Manufacturer/listing allowance is the controlling exception: if the accessory (hearth extension assembly, gasketed door, or decorative shroud) is specifically listed and labeled for use with that exact factory-built fireplace/chimney system and installed exactly per the listing/manufacturer instructions, the accessory is permitted. § R1004.2, § R1004.5, § R1004.3 .
  • For chimneys, R1005.2 and related mechanical-code text also require listed shrouds where permitted — check both the fireplace and chimney listings and instructions. § R1005.2 .
  • If the unit is a masonry fireplace (not factory-built) the CRC’s masonry hearth provisions apply (see § R1001.9–R1001.10), not the factory-built rules — do not conflate the two. § R1001.9, § R1001.10

If the code excerpt needed to resolve a specific installation detail is not in the sections you provided (for example, the listing’s required numeric hearth extension for a particular appliance model), you must rely on the manufacturer’s listing and test-standard documents (UL 1618, UL 127) because the CRC defers to those listings for factory-built systems. § R1004.2, § R1004.5, § R1004.3

Common mistakes

  • Assuming masonry hearth dimensions apply to factory-built fireplaces (they don’t — factory-built units follow their listing). See contrast between § R1004.2 and § R1001.10.
  • Installing a gasketed/airtight door without verifying that the entire fireplace system is listed for that door (a code violation per § R1004.5).
  • Adding a decorative chimney shroud that is not listed for that specific model or that is installed contrary to the manufacturer’s instructions (prohibited by § R1004.3 and echoed in § R1005.2).
  • Relying on generic aftermarket parts or “universal” accessories instead of the specific listed assemblies required by the fireplace/chimney listing.

Worked example — concrete scenario

Scenario: You have a listed factory-built fireplace (Model F-100) with a manufacturer listing that shows a listed hearth extension assembly and allows only non-gasketed doors. You want to (a) reduce the front hearth extension to 12 inches, (b) install a gasketed glass door, and (c) add a decorative aluminum shroud at the chimney top.

Applying the CRC:

  1. Hearth extension: Because § R1004.2 requires installation in accordance with the fireplace listing, you cannot reduce the extension to 12 in. if the listing specifies a larger extension — the listing controls. § R1004.2 .
  2. Gasketed door: § R1004.5 forbids adding a gasketed door unless the fireplace system is specifically tested, listed and labeled for that door per UL 127. If Model F-100’s listing does not include a gasketed door configuration, the door may not be installed. § R1004.5 .
  3. Decorative shroud: You may only add the aluminum shroud if the shroud is listed and labeled for Model F-100 and installed per the manufacturer’s instructions; an off-the-shelf shroud not listed for that model is not allowed by § R1004.3. § R1004.3 .

Outcome: Unless Model F-100’s listing explicitly permits the 12 in. hearth extension, shows the gasketed door configuration, and lists the specific shroud, none of the proposed changes are code-compliant.

Related provisions

  • § R1004.2 — Hearth extensions for factory-built fireplaces (UL 1618).
  • § R1004.3 — Decorative shrouds for factory-built fireplaces (listed & labeled requirement).
  • § R1004.5 — Gasketed fireplace doors on factory-built fireplaces (UL 127 testing/listing requirement).
  • § R1005.2 — Decorative shrouds at termination of factory-built chimneys (parallel restriction).
  • § R1001.9 — R1001.10 — Hearth and hearth extension dimensions for masonry fireplaces (contrast with factory-built rules).

Code references

Grounded in the retrieved California Residential Code — click a citation to read the verbatim passage:

  • CRC § 25.4 High relevance — show source text

    FIGURE R1003.20—CHIMNEY CRICKET

    AIRSPACE

    ROOF LINE

    For SI: 1 inch = 25.4 mm.

    FLUE LINER Col2 Col3 Col4 Col5
    1 IN.
    AIRS    		 1 IN.
    AIRS    		 1 IN.
    AIRS    		 1 IN.
    AIRS    		 1 IN.
    AIRS
    W W W W W

    2025 CALIFORNIA RESIDENTIAL CODE 10-11

    on Jul 18, 2025 11:14 AM (CDT) THEREUNDER.

    �

    CHIMNEYS AND FIREPLACES

    SECTION R1004—FACTORY-BUILT FIREPLACES

    R1004.1 General. Factory-built fireplaces shall be listed and labeled and shall be installed in accordance with the conditions of the listing. Factory-built fireplaces shall be tested in accordance with UL 127.

    R1004.1.1 Factory-built wood burning fireplaces. Factory-built wood burning fireplaces shall be qualified at the U.S. EPA’s Volun- tary Fireplace Program Phase 2 emissions level and be in accordance with the California Green Building Standards Code, Chapter 4, Division 4.5.

    R1004.2 Hearth extensions. Hearth extensions of approved factory-built fireplaces shall be installed in accordance with the listing of the fireplace. The hearth extension shall be readily distinguishable from the surrounding floor area. Listed and labeled hearth extensions shall comply with UL 1618.

    R1004.3 Decorative shrouds. Decorative shrouds shall not be installed at the termination of chimneys for factory-built fireplaces except where the shrouds are listed and labeled for use with the specific factory-built fireplace system and installed in accordance with the manufacturer’s instructions.

    R1004.5 Gasketed fireplace doors. A gasketed fireplace door shall not be installed on a factory-built fireplace except where the fireplace system has been specifically tested, listed and labeled for such use in accordance with UL 127.

    SECTION R1005—FACTORY-BUILT CHIMNEYS

    R1005.1 Listing. Factory-built chimneys shall be listed and labeled and shall be installed and terminated in accordance with the manufacturer’s installation instructions.

    R1005.2 Decorative shrouds. Decorative shrouds shall not be installed at the termination of factory-built chimneys except where the shrouds are listed and labeled for use with the specific factory-built chimney system and installed in accordance with the manufacturer’s installation instructions.

    R1005.3 Solid-fuel appliances. Factory-built chimneys installed in dwelling units with solid-fuel-burning appliances shall comply with the Type HT requirements of UL 103 and shall be marked “Type HT” and “Residential Type and Building Heating Appliance Chimney.”

    Exception: Chimneys for use with open combustion chamber fireplaces shall comply with the requirements of UL 103 and shall be marked “Residential Type and Building Heating Appliance Chimney.”

    Chimneys for use with open combustion chamber appliances installed in buildings other than dwelling units shall comply with the requirements of UL 103 and shall be marked “Building Heating Appliance Chimney” or “Residential Type and Building Heating Appliance Chimney.”

    R1005.4 Factory-built fireplaces. Chimneys for use with factory-built fireplaces shall comply with the requirements of UL 127.

  • CRC § 0.52 High relevance — show source text

    R1004.5 Gasketed fireplace doors. A gasketed fireplace door shall not be installed on a factory-built fireplace except where the fireplace system has been specifically tested, listed and labeled for such use in accordance with UL 127.

    SECTION R1005—FACTORY-BUILT CHIMNEYS

    R1005.1 Listing. Factory-built chimneys shall be listed and labeled and shall be installed and terminated in accordance with the manufacturer’s installation instructions.

    R1005.2 Decorative shrouds. Decorative shrouds shall not be installed at the termination of factory-built chimneys except where the shrouds are listed and labeled for use with the specific factory-built chimney system and installed in accordance with the manufacturer’s installation instructions.

    R1005.3 Solid-fuel appliances. Factory-built chimneys installed in dwelling units with solid-fuel-burning appliances shall comply with the Type HT requirements of UL 103 and shall be marked “Type HT” and “Residential Type and Building Heating Appliance Chimney.”

    Exception: Chimneys for use with open combustion chamber fireplaces shall comply with the requirements of UL 103 and shall be marked “Residential Type and Building Heating Appliance Chimney.”

    Chimneys for use with open combustion chamber appliances installed in buildings other than dwelling units shall comply with the requirements of UL 103 and shall be marked “Building Heating Appliance Chimney” or “Residential Type and Building Heating Appliance Chimney.”

    R1005.4 Factory-built fireplaces. Chimneys for use with factory-built fireplaces shall comply with the requirements of UL 127.

    R1005.5 Support. Where factory-built chimneys are supported by structural members, such as joists and rafters, those members shall be designed to support the additional load.

    R1005.6 Medium-heat appliances. Factory-built chimneys for medium-heat appliances producing flue gases having a temperature above 1,000°F (538°C), measured at the entrance to the chimney, shall comply with UL 959.

    R1005.7 Factory-built chimney offsets. Where a factory-built chimney assembly incorporates offsets, no part of the chimney shall be at an angle of more than 30 degrees (0.52 rad) from vertical at any point in the assembly and the chimney assembly shall not include more than four elbows.

    R1005.8 Insulation shield. Where factory-built chimneys pass through insulated assemblies, an insulation shield constructed of steel having a thickness of not less than 0.0187 inch (0.4712 mm) (No. 26 gage) shall be installed to provide clearance between the chimney and the insulation material. The clearance shall be not less than the clearance to combustibles specified by the chimney manufacturer’s installation instructions. Where chimneys pass through attic space, the shield shall terminate not less than 2 inches (51 mm) above the insulation materials and shall be secured in place to prevent displacement. Insulation shields provided as part of a listed chimney system shall be installed in accordance with the manufacturer’s installation instructions.

    R1005.9 Factory-built chimney offsets. Where a fireplace manufacturer’s instructions do not address factory-built chimney offsets, no part of the chimney shall be at an angle of more than 30 degrees (0.52 rad) from vertical at any point in the assembly and the chimney assembly shall not include more than four elbows.

    SECTION R1006—EXTERIOR AIR SUPPLY

  • CRC § 605.1.5.2 High relevance — show source text

    605.1.5.2 Operating instructions. After completing the installation, the installer shall instruct the owner or operator in the proper operation of the equipment. The installer shall furnish the owner or operator with the manufacturer’s operating instructions.

    605.1.6 Clearances. Working clearances between fuel-fired appliances and electrical panelboards and equipment shall be in accordance with the California Electrical Code . Clearances between oil-fired equipment and oil supply tanks shall be in accordance with the California Electrical Code .

    605.2 Abatement of unsafe conditions. The fire code official is authorized to order that measures be taken to prevent the operation of any existing stove, oven, furnace, incinerator, boiler or any other heat-producing device or appliance found to be defective or in violation of code requirements for existing appliances after giving notice to this effect to any person, owner, firm or agent or operator in charge of the same. The fire code official is authorized to take measures to prevent the operation of any device or appliance without notice when inspection shows the existence of an immediate fire hazard or when imperiling human life. The defective device shall remain withdrawn from service until all necessary repairs or alterations have been made or replaced in accordance with Section 605.1.

    605.2.1 Chimneys and appliances. Chimneys, vents, incinerators, smokestacks or similar devices for conveying smoke or hot gases to the outer air and the appliances such as stoves, furnaces, fireboxes or boilers to which such devices are connected, shall be maintained so as not to create a fire hazard.

    605.2.1.1 Masonry chimneys. Masonry chimneys that, upon inspection, are found to be without a flue liner and that have open mortar joints which will permit smoke or gases to be discharged into the building, or which are cracked as to be dangerous, shall be repaired or relined with a listed chimney liner system installed in accordance with the manufacturer’s instructions and the California Mechanical Code or a flue lining system installed in accordance with the requirements of the California Build- ing Code and appropriate for the intended class of chimney service.

    605.2.1.2 Metal chimneys. Metal chimneys that are corroded or improperly supported shall be repaired or replaced in accordance with the California Mechanical Code .

    605.2.1.3 Decorative shrouds. Decorative shrouds installed at the termination of factory-built chimneys or vents shall be removed except where such shrouds are listed and labeled for use with the specific factory-built chimney system and are installed in accordance with the chimney or vent manufacturer’s instructions and the California Mechanical Code or Interna- tional Fuel Gas Code .

    605.2.1.4 Factory-built chimney and vent systems. Existing factory-built chimneys and vent systems that are damaged, corroded or improperly supported shall be repaired or replaced in accordance with the California Mechanical Code .

    605.2.1.5 Connectors. Existing chimney and vent connectors that are damaged, corroded or improperly supported shall be repaired or replaced in accordance with the California Mechanical Code .

    605.3 Chimneys and vents. Masonry chimneys shall be constructed in accordance with the California Building Code . Factory-built chimneys and vent systems serving solid-fuel-fired appliances or oil-fired appliances shall be installed in accordance with the Califor- nia Mechanical Code . Metal chimneys shall be constructed and installed in accordance with the California Mechanical Code . Factorybuilt chimneys and vent systems serving gas-fired appliances shall be installed in accordance with the International Fuel Gas Code .

  • CRC § 605.2.1.2 Medium relevance — show source text

    605.2.1.2 Metal chimneys. Metal chimneys that are corroded or improperly supported shall be repaired or replaced in accordance with the California Mechanical Code .

    605.2.1.3 Decorative shrouds. Decorative shrouds installed at the termination of factory-built chimneys or vents shall be removed except where such shrouds are listed and labeled for use with the specific factory-built chimney system and are installed in accordance with the chimney or vent manufacturer’s instructions and the California Mechanical Code or Interna- tional Fuel Gas Code .

    605.2.1.4 Factory-built chimney and vent systems. Existing factory-built chimneys and vent systems that are damaged, corroded or improperly supported shall be repaired or replaced in accordance with the California Mechanical Code .

    605.2.1.5 Connectors. Existing chimney and vent connectors that are damaged, corroded or improperly supported shall be repaired or replaced in accordance with the California Mechanical Code .

    605.3 Chimneys and vents. Masonry chimneys shall be constructed in accordance with the California Building Code . Factory-built chimneys and vent systems serving solid-fuel-fired appliances or oil-fired appliances shall be installed in accordance with the Califor- nia Mechanical Code . Metal chimneys shall be constructed and installed in accordance with the California Mechanical Code . Factorybuilt chimneys and vent systems serving gas-fired appliances shall be installed in accordance with the International Fuel Gas Code .

    605.4 Fuel oil storage systems. Fuel oil storage systems for combustion engines and gas turbines shall be installed and maintained in accordance with this code. Tanks and fuel oil piping systems for building heating systems shall be installed in accordance with this section and NFPA 31. Tanks and fuel oil piping systems for generators and fire pumps shall be installed in accordance with Section 605.4.2 or Chapter 57.

    605.4.1 Fuel oil storage in outside, above-ground tanks. Where connected to a fuel oil piping system, the maximum amount of fuel oil storage allowed outside above ground without additional protection shall be 660 gallons (2498 L). The storage of fuel oil above ground for building heating systems in quantities exceeding 660 gallons (2498 L) shall comply with NFPA 31. The storage of fuel oil above ground for combustion engines and gas turbines in portable tanks exceeding a capacity of 660 gallons (2498 L) shall comply with Chapter 57.

    605.4.1.1 Approval. Outdoor fuel oil storage tanks shall be in accordance with UL 80, UL 142 or UL 2085.

    605.4.2 Fuel oil storage inside buildings. Fuel oil storage inside buildings shall comply with Sections 605.4.2.2 through 605.4.2.8 or Chapter 57.

    605.4.2.1 Approval. Indoor fuel oil storage tanks shall be in accordance with UL 80, UL 142 or UL 2085.

  • CRC § 1.1 Medium relevance — show source text

    103—2010: Factory-built Chimneys for Residential Type and Building Heating Appliances—with Revisions through September 2021

    R202, R1005.3

    127—2011: Factory-Built Fireplaces—with Revisions through February 2020

    R1001.11, R1004.1, R1004.4, R1004.5, R1005.4

    217—2015: Smoke Alarms—with Revisions through April 2021

    R310.1.1, R311.1.1

    263—2011: Fire Test of Building Construction and Materials—with Revisions through August 2021 Table R302.1(2), R302.2, R302.2.1, R302.2.2, R302.4.1, R302.11.1, R606.2.2

    268—2016: Smoke Detectors for Fire Alarm Systems—with Revisions through October 2019

    R310.7.1, R310.7.4, R311.7.4

    325—2017: Door, Drapery, Gate, Louver and Window Operators and Systems—with Revisions through February 2020

    R317.4

    580—2006: Test for Uplift Resistance of Roof Assemblies—with Revisions through March 2019

    R905.4.4.1, R905.9.4, R905.10.5, R905.11.4, R905.12.4, R905.13.4, R905.14.4

    641—2010: Type L Low-Temperature Venting Systems—with Revisions through April 2018

    R202, R1003.11.5

    723—2018: Standard for Test for Surface Burning Characteristics of Building Materials

    R202, R302.9.3, R302.9.4, R302.10.1, R302.10.2, R302.15, R303.3, R303.5.9, R303.5.11, R507.2.2.2, R703.14.3

    790— Edition 9—2022 : Standard Test Methods for Fire Tests of Roof Coverings—with Revisions through October 2018

    R302.2.4, R902.1

    907—2016: Fireplace Accessories

    R1001.13

    959—2010: Medium Heat Appliance Factory-Built Chimneys—with Revisions through August 2019

    R1005.6

    1040—1996: Fire Test of Insulated Wall Construction—with Revisions through April 2017

    R303.6

    1256—2002: Fire Test of Roof Deck Construction—with Revisions through August 2018

    R906.1

    1479—2015: Fire Tests of Penetration Firestops—with Revisions through May 2021

    R302.4.1.2

    1482—2011: Solid-Fuel Type Room Heaters—with Revisions through February 2020

    R1002.2, R1002.5

    1618—2015: Wall Protectors, Floor Protectors, and Hearth Extensions—with Revisions through January 2018

    R1004.2

    1703—2002: Flat-Plate Photovoltaic Modules and Panels—with Revisions through November 2019

    R329.3.1, R902.4

    1715—1997: Fire Test of Interior Finish Material—with revisions through April 2017

    R303.6

  • CRC § 12.4.5.2 Medium relevance — show source text

    (2) The vent system shall be installed such that no fittings or joints between sections are installed in the above-ceiling space.

    (3) The venting system shall be installed in a conduit or enclosure with joints between the interior of the enclosure and the ceiling space sealed. [NFPA 54:12.4.5.2] 802.4 Type of Venting System to be Used. The type of venting system to be used shall be in accordance with Table 802.4. [NFPA 54:12.5.1]

    802.4.1 Plastic Piping. Where plastic piping is used to vent an appliance, the appliance shall be listed for use with such venting materials and the appliance manufacturer’s installation instructions shall identify the specific plastic piping material. The plastic pipe venting materials shall be labeled in accordance with the product standards specified by the appliance manufacturer or shall be listed and labeled in accordance with UL 1738. [NFPA 54:12.5.2]

    802.4.2 Plastic Vent Joints. Plastic pipe and fittings used to vent appliances shall be installed in accordance with the appliance manufacturer’s installation instructions. Plastic pipe venting materials listed and labeled in accordance with UL 1738 shall be installed in accordance

    with the vent manufacturer’s installation instructions. Where primer is required, it shall be of a contrasting color.

    [NFPA 54:12.5.3]

    802.4.3 Special Gas Vents. Special gas vents shall be listed and labeled in accordance with UL 1738 and installed in accordance with the special gas vent manufacturer’s installation instructions. [NFPA 54:12.5.4]

    802.5 Masonry, Metal, and Factory-Built Chimneys. Chimneys shall be installed in accordance with Section 802.5.1 through Section 802.5.3.

    802.5.1 Factory-Built Chimneys. Factory-built chimneys shall be listed in accordance with UL 103, UL 959, or UL 2561. Factory-built chimneys used to vent appliances that operate at positive vent pressure shall be listed for such application. [NFPA 54:12.6.1.1]

    802.5.1.1 Decorative Shrouds. Decorative shrouds addressed in Section 802.5.4.3 shall comply with UL 103 for factory-built residential chimneys, UL 127 for factory-built fireplaces, or UL 1482 for solid-fuel room heaters.

    802.5.2 Metal Chimneys. Metal chimneys shall be built and installed in accordance with NFPA 211. [NFPA 54:12.6.1.2]

    802.5.3 Masonry Chimneys. Masonry chimneys shall be built and installed in accordance with NFPA 211 and lined with one of the following:

    (1) Approved clay flue lining.

    (2) A chimney lining system listed and labeled in accordance with UL 1777.

    (3) Other approved material that resists corrosion, erosion, softening, or cracking from vent gases at temperatures up to 1800°F (982°C).

    Exception: Masonry chimney flues lined with a chimney lining system specifically listed for use with listed appliances with draft hoods, Category I appliances, and

    154 2025 CALIFORNIA MECHANICAL CODE

    ), Copyright © 2025 IAPMO, and may not be used for any other purpose or distributed to any other persons or parties.

    CHIMNEYS AND VENTS

  • CRC § 4.1 Medium relevance — show source text

    4.1
    and Section
    509.4.3| |










    Appliances that can be
    converted to use solid
    fuel

    Unlisted combination
    gas- and oil-burning
    appliances

    Combination gas- and
    solid fuel-burning
    appliances

    Appliances listed for
    use with chimneys only

    Unlisted appliances|Chimney|Section 509.5| |

    Listed combination
    gas- and oil-burning
    appliances|Type L vent|Section 509.6| |

    Listed combination
    gas- and oil-burning
    appliances|Chimney|Section 509.5| |

    Decorative appliance in
    vented fireplace|Chimney|UMC Section
    911.2| |
    Gas-fired toilets|Single-wall metal
    pipe|Section 509.7| |
    Direct-vent appliances|—|Section 509.2.6| |
    Appliances with
    integral vents|—|Section 509.2.7|

    509.4.2 Plastic Vent Joints. Plastic pipe and fittings used to vent appliances shall be installed in accordance with the appliance manufacturer’s installation instructions. Plastic pipe venting materials listed and labeled in accordance with UL 1738 shall be installed in accor dance with the vent manufacturer’s installation instruc

    TABLE 509.4

    TYPE OF VENTING SYSTEM TO BE USED {NFPA 54: TABLE 12.5.1}

    92 2025 CALIFORNIA PLUMBING CODE

    ), Copyright © 2025 IAPMO, and may not be used for any other purpose or distributed to any other persons or parties.

    WATER HEATERS

    tions. Where primer is required, it shall be of a contrasting color. [NFPA 54:12.5.3] 509.4.3 Special Gas Vents. Special gas vents shall be listed and labeled in accordance with UL 1738 and installed in accordance with the special gas vent manufacturer’s installation instructions. [NFPA 54:12.5.4] 509.5 Masonry, Metal, and Factory-Built Chimneys. Chimneys shall be installed in accordance with Section 509.5.1 through Section 509.5.3. 509.5.1 Factory-Built Chimneys. Factory-built chimneys shall be listed in accordance with UL 103, UL 959, or UL 2561. Factory-built chimneys used to vent appliances that operate at positive vent pressure shall be listed for such application. [NFPA 54:12.6.1.1]

    509.5.1.1 Decorative Shrouds. Decorative

    shrouds addressed in Section 509.5.4.3 shall comply with UL 103 for factory -built residential chim neys. 509.5.2 Metal Chimneys. Metal chimneys shall be built and installed in accordance with NFPA 211. [NFPA 54:12.6.1.2] 509.5.3 Masonry Chimneys. Masonry chimneys shall be built and installed in accordance with NFPA 211 and lined with one of the following:

    (1) Approved clay flue lining

  • CRC § 501.7 Medium relevance — show source text

    In firefighter breathing air

    replenishment systems . . . . . . . . . . . . . . . . . .F 501.7,

    F 601.5.1, F 701.3

    In fuel gas systems . . . . . . . . . . . . . . . . . . . . . .1208.7.1

    In medical gas and

    medical vacuum systems . . . . . . . . .1311.5(2), 1313.5

    In water supply systems . . . . . . . . . .Table 603.2, 603.3,

    608.3

    CHEMICAL RESISTANT GLASS PIPE . . . . . . . . . . . .811.2

    CHEMICAL WASTES . . . . . . . . . . . . . . . . . . . . .205.0, 811.0

    CHIMNEYS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .509.5

    Cleanouts . . . . . . . . . . . . . . . . . . . . .509.5.6.2, 509.5.9

    Decorative Shrouds . . . . . . . . . . . .509.5.1.1, 509.5.4.3

    Definition . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .205.0

    Existing . . . . . . . . . . . . . . . . . . . . . . .509.5.6, 509.5.6.3

    Factory-built . . . . . . . . . . . . . . . . . . . . . . . . . . . .509.5.1

    Masonry . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .509.5.3

    Metal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .509.5.2

    Size . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .509.5.5

    Support . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .509.5.8

    Termination . . . . . . . . . . . . . . . . . . . . . . . . . . . . .509.5.4

    CHLORINATED POLYVINYL

    CHLORIDE (CPVC) PIPE OR TUBING

    Approved standards, water supply . . . . . . . .Table 604.1

    Definition . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .205.0

    Joining and connections . . . . . . . . . . . . . . . .(see Joints

    and connections)

    Installation, residential . . . . . . . . . . . . . . . . . . . . .604.1.1

    CHLORINATED POLYVINYL

  • CRC § 1.1.1 Medium relevance — show source text
    1. Performance. This heading is subdivided into two columns. The column labeled “Load” will either list the load that the building element was subjected to during the fire test or it will contain a note number which will list the load and any other significant details. If the building element was not subjected to a load during the test, this column will contain “n/a,” which means “not applicable.”

    The second column under performance is labeled “Time” and denotes the actual fire endurance time observed in the fire test.

    1. Reference Number. This heading is subdivided into three columns: Pre-BMS-92; BMS-92; and Post-BMS-92. The table entry under this column is the number in the Bibliography of the original source reference for the test data.
    2. Notes. Notes are provided at the end of each table to allow a more detailed explanation of certain aspects of the test. In certain tables the notes given to this column have also been listed under the “Construction Details” and/or “Load” columns.
    3. Rec. Hours. This column lists the recommended fire endurance rating, in hours, of a building element. In some cases, the recommended fire endurance will be less than that listed under the “Time” column. In no case is the “Rec. Hours” greater than given in the “Time” column.
    EXAMPLE ENTRY Col2 Col3 Col4 Col5 Col6 Col7 Col8 Col9 Col10
    ITEM
    CODE    		 THICKNESS CONSTRUCTION DETAILS PERFORMANCE PERFORMANCE REFERENCE NUMBER REFERENCE NUMBER REFERENCE NUMBER NOTES REC.
    HOURS
    ITEM
    CODE    		 THICKNESS CONSTRUCTION DETAILS LOAD TIME PRE-
    BMS-92    		 BMS-92 POST-
    BMS-92    		 POST-
    BMS-92    		 POST-
    BMS-92
    W-4-
    M-50    		 45/8″ Core: structural clay tile, see Notes 12,
    16, 21; facings on unexposed side
    only, see Note 18.    		 N/A 25 min 1 3, 4, 24 1/3

    2025 CALIFORNIA EXISTING BUILDING CODE RESOURCE A-19

    on Jul 18, 2025 11:14 AM (CDT) THEREUNDER.

    RESOURCE A—GUIDELINES ON FIRE RATINGS OF ARCHAIC MATERIALS AND ASSEMBLIES

    SECTION I—WALLS

    FIGURE 1.1.1

    MASONRY WALLS 0 ″ TO LESS THAN 4 ″ THICK

    10

    5

    0

  • CRC § 12.5.3 Medium relevance — show source text

    92 2025 CALIFORNIA PLUMBING CODE

    ), Copyright © 2025 IAPMO, and may not be used for any other purpose or distributed to any other persons or parties.

    WATER HEATERS

    tions. Where primer is required, it shall be of a contrasting color. [NFPA 54:12.5.3] 509.4.3 Special Gas Vents. Special gas vents shall be listed and labeled in accordance with UL 1738 and installed in accordance with the special gas vent manufacturer’s installation instructions. [NFPA 54:12.5.4] 509.5 Masonry, Metal, and Factory-Built Chimneys. Chimneys shall be installed in accordance with Section 509.5.1 through Section 509.5.3. 509.5.1 Factory-Built Chimneys. Factory-built chimneys shall be listed in accordance with UL 103, UL 959, or UL 2561. Factory-built chimneys used to vent appliances that operate at positive vent pressure shall be listed for such application. [NFPA 54:12.6.1.1]

    509.5.1.1 Decorative Shrouds. Decorative

    shrouds addressed in Section 509.5.4.3 shall comply with UL 103 for factory -built residential chim neys. 509.5.2 Metal Chimneys. Metal chimneys shall be built and installed in accordance with NFPA 211. [NFPA 54:12.6.1.2] 509.5.3 Masonry Chimneys. Masonry chimneys shall be built and installed in accordance with NFPA 211 and lined with one of the following:

    (1) Approved clay flue lining

    (2) A chimney lining system listed and labeled in accordance with UL 1777

    (3) Other approved material that resists corrosion, erosion, softening, or cracking from vent gases at temperatures up to 1800°F (982°C)

    Exception: Masonry chimney flues lined with a chimney lining system specifically listed for use with listed appliances with draft hoods, Category I appliances, and other appliances listed for use with Type B vents shall be permitted. The liner shall be installed in accordance with the liner manufacturer’s installation instructions. A permanent identifying label shall be attached at the point where the connection is to be made to the liner. The label shall read “This chimney liner is for appliances that burn gas only. Do not connect to solid or liquid fuel-burning appliances or incinerators.” [NFPA 54:12.6.1.3] 509.5.4 Termination. A chimney for residential-type or low-heat appliances shall extend at least 3 feet (914 mm) above the highest point where it passes through a roof of a building and at least 2 feet (610 mm) higher than any portion of a building within a horizontal distance of 10 feet (3048 mm). [NFPA 54:12.6.2.1] (See Figure 509.5.4) 509.5.4.1 Medium-Heat Gas Appliances. A chimney for medium-heat appliances shall extend at least 10 feet (3048 mm) higher than any portion of any building within 25 feet (7620 mm). [NFPA 54:12.6.2.2] **509.5.4.2 Chimney Height.

  • CRC § 1.11. Medium relevance — show source text
    • The California Code of Regulations (CCR), Title 19, Division 1 provisions that are found in the California Fire Code are a reprint from the current CCR, Title 19, Division 1 text for the code user’s convenience only. The scope, applicability and appeals procedures of CCR, Title 19, Division I remain the same. The state agency does not adopt sections identified by the following symbol: The Office of the State Fire Marshal’s adoption of this chapter or individual sections is applicable to structures regulated by other state agencies pursuant to Section 1.11.

    2025 CALIFORNIA FIRE CODE 7-1

    on Jul 18, 2025 11:14 AM (CDT) THEREUNDER.

    7-2 2025 CALIFORNIA FIRE CODE

    on Jul 18, 2025 11:14 AM (CDT) THEREUNDER.

    7 FIRE AND SMOKE PROTECTION FEATURES

    User notes:

    About this chapter: Chapter 7 provides requirements to maintain the fire-resistance ratings of building elements and to limit fire spread. Section 701 addresses the maintenance of and owner’s responsibility for construction elements such as fire barriers and smoke barriers. The rest of the chapter deals with various aspects that also must be maintained to achieve overall fire resistance of the main fire- and smoke-resistive features. These include penetrations, joint protection, door and window openings, and duct and air transfer opening protection.

    SECTION 701—GENERAL

    701.1 Scope. The provisions of this chapter shall govern the inspection and maintenance of the materials, systems and assemblies used for structural fire resistance, fire-resistance-rated construction separation of adjacent spaces and construction installed to resist the passage of smoke to safeguard against the spread of fire and smoke within a building and the spread of fire to or from buildings. New buildings shall comply with the California Building Code.

    701.2 Fire-resistance-rated construction. The fire-resistance rating of the following fire-resistance-rated construction shall be maintained:

    1. Structural members.

    2. Exterior walls.

    3. Fire walls, fire barriers, fire partitions.

    4. Horizontal assemblies.

    5. Shaft enclosures.

    701.2.1 Hanging displays. The hanging and displaying of salable goods and other decorative materials from acoustical ceiling systems that are part of a fire-resistance-rated horizontal assembly shall be prohibited.

    701.3 Smoke barriers. The fire-resistance rating and smoke-resistant characteristics of smoke barriers shall be maintained.

    701.4 Smoke partitions. The smoke-resistant characteristics of smoke partitions shall be maintained.

    701.5 Maintaining protection. Materials, systems and devices used to repair or protect breaches and openings in fire-resistance-rated construction and construction installed to resist the passage of smoke shall be maintained in accordance with Sections 703 through 707.

    701.6 Owner’s responsibility. The owner shall maintain an inventory of all required fire-resistance-rated construction, construction installed to resist the passage of smoke and the construction included in Sections 703 through 707 and Sections 602.4.1 and 602.4.2 of the California Building Code . Such construction shall be visually inspected by the owner annually and properly repaired, restored or replaced where damaged, altered, breached or penetrated. Where concealed, such elements shall not be required to be visually inspected by the owner unless the concealed space is accessible by the removal or movement of a panel, access door, ceiling tile or similar movable entry to the space.

  • CRC § 1.11. Medium relevance — show source text
    Adopting Agency BSC BSC-
    CG    		 SFM HCD Col6 Col7 DSA Col9 Col10 OSHPD Col12 Col13 Col14 Col15 Col16 Col17 BSCC DPH AGR DWR CEC CA SL SLC
    Adopting Agency BSC BSC-
    CG    		 SFM 1 2 1/AC AC SS SS/CC 1 1R 2 3 4 5 6 6 6 6 6 6 6 6 6
    Adopt Entire Chapter
    Adopt Entire Chapter as
    amended (amended
    sections listed below)
    Adopt only those sections
    that are listed below
    Chapter / Section

    The state agency does not adopt sections identified with the following symbol: † The Office of the State Fire Marshal’s adoption of this chapter or individual sections is applicable to structures regulated by other state agencies pursuant to Section 1.11.

    2025 CALIFORNIA EXISTING BUILDING CODE APPENDIX C-25

    on Jul 18, 2025 11:14 AM (CDT) THEREUNDER.

    APPENDIX C-26 2025 CALIFORNIA EXISTING BUILDING CODE

    on Jul 18, 2025 11:14 AM (CDT) THEREUNDER.

    APPENDIX C—GUIDELINES FOR THE WIND RETROFIT OF EXISTING BUILDINGS

    CHAPTER C2 ROOF DECK FASTENING FOR HIGH-WIND AREAS

    SECTION C201—GENERAL

    [BS] C201.1 Purpose. This chapter provides prescriptive methods for partial structural retrofit of an existing building to increase its resistance to wind loads. It is intended for voluntary use where the basic wind speed, V, is greater than 130 mph (58 m/s) in accordance with Figure 1609.3(2) of the California Building Code and for reference by mitigation programs. The provisions of this chapter do not necessarily satisfy requirements for new construction. Unless specifically cited, the provisions of this chapter do not necessarily satisfy requirements for structural improvements triggered by addition, alteration, repair, change of occupancy, building relocation or other circumstances.

    [BS] C201.2 Eligible conditions. The provisions of this chapter are applicable only to buildings that meet either of the following eligibility requirements:

    1. Buildings assigned to Risk Category I or II in accordance with Table 1604.5 of the California Building Code .
    2. Buildings within the scope of the California Residential Code .

    SECTION C202—ROOF DECK ATTACHMENT FOR WOOD ROOFS

Frequently asked questions

Can I follow the masonry hearth dimensions in the CRC for a factory-built fireplace?

No. Factory-built fireplaces defer to their listing and UL test standards for hearth extensions; masonry hearth dimensions in § R1001.10 apply to masonry fireplaces, not factory-built units. § R1004.2, § R1001.10

My fireplace manufacturer provided a “recommended” hearth extension — is that binding?

If the recommendation is part of the fireplace’s listing or manufacturer installation instructions (the listing), it is binding per § R1004.2; the CRC requires installation in accordance with the listing. § R1004.2

Can I retrofit a gasketed door if a dealer sold me a door kit that fits?

Only if the fireplace system (not just the door) has been specifically tested and listed for that gasketed-door configuration in accordance with UL 127. Otherwise it is not allowed by § R1004.5.

Is a decorative shroud allowed if it’s made from noncombustible material?

Material alone is not enough. The shroud must be listed and labeled for use with that specific factory-built fireplace or chimney system and installed per the manufacturer’s instructions. § R1004.3, § R1005.2

Where do I find the exact numeric dimensions for my factory-built hearth extension?

The exact dimensions are in the fireplace’s listing and manufacturer installation instructions (and the listed hearth extension standard, UL 1618). The CRC directs you to follow the listing rather than provide alternate numbers for factory-built systems. § R1004.2

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What listing, labeling and installation requirements apply to factory-built fireplaces and chimneys?

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What limits apply to chimney offsets, insulation shields and elbow counts for factory-built chimneys?

Factory-built Fireplaces & Chimneys

California Residential Code